I do that in Wings3d all the time, and whenever I switch back to Blender I find myself trying to zoom with the wheel there too... It would be great to have your patch included in the official codebase.

The little wheel between the left & right button operates as a third button,
which you can either press or roll up and down.

Blender is all about efficiency in controls. When you master the hotkeys and
use a three button mouse, you can work extremely fast. Mousewheel support
gives an extra input device, which allows you to work even faster.

In every 2d and 3d windowspace you can use the wheel to zoom in and out.
You can scroll through the items in the file and image selectors and in the
text editor you can browse through the document. I mean, Blender is so
incredible, it even works with the button menu's.